1. Jemerson Pedernal IT 2.1 FUNDAMENTALS OF DATABASE APPLICATIONS by PEDERNAL, JEMERSON G. [BS-Computer Science] Palawan State University Computer Network Specialist

2. Jemerson Pedernal Chapter 1 Databases and Information Models 1.1 What is a database? 1.2 What is a database management system? 1.3 Introduction to information models and data models 1.4 Types of information models 1.5 Typical roles and career path for database professionals

3. Jemerson Pedernal Data is one of the most critical assets of any business. Data, as important as it is, needs robust, secure, and highly available software that can store and process it quickly. Database software usage is pervasive, yet it is taken for granted by the billions of daily users worldwide.

4. Jemerson Pedernal 1.1 Database A database is a repository of data, designed to support efficient data storage, retrieval and maintenance. A database may be specialized to store binary files, documents, images, videos, relational data, multidimensional data, transactional data, analytic data, or geographic data to name a few.

5. Jemerson Pedernal 1.2 Database Management System database management system, or simply DBMS, is a set of software tools that control access, organize, store, manage, retrieve and maintain data in a database. In practical use, the terms database, database server, database system, data server, and database management systems are often used interchangeably.

6. Jemerson Pedernal 1.3 Introduction to information models and data models An information model is an abstract, formal representation of entities that includes their properties, relationships and the operations that can be performed on them. The primary motivation behind the concept is to formalize the description of a problem domain without constraining how that description will be mapped to an actual implementation in software.

7. Jemerson Pedernal Modeling allows for compatibility with its predecessor models and has provisions for future extensions. An Information Model should hide all protocol and implementation details. An Information Model defines relationships between managed objects A data model is the blueprint of any database system.

8. Jemerson Pedernal Figure 1.1 - Relationship between an Information Model and a Data Model

9. Jemerson Pedernal 1.4 Types of information models Information model proposals can be split into nine historical epochs: Network (CODASYL): 1970’s Hierarchical (IMS): late 1960’s and 1970’s Relational: 1970’s and early 1980’s Entity-Relationship: 1970’s Extended Relational: 1980’s Semantic: late 1970’s and 1980’s Object-oriented: late 1980’s and early 1990’s Object-relational: late 1980’s and early 1990’s Semi-structured (XML): late 1990’s to the present

10. Jemerson Pedernal Network Model

11. Jemerson Pedernal Hierarchical model

12. Jemerson Pedernal Relational model It has a solid mathematic foundation based on sets theory and predicate calculus and is the most used data model for databases today.

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14. Entity-Relationship model Entities are objects that have an existence independent of any other entities in the database. Entities have attributes, which are the data elements that characterize the entity. One or more of these attributes could be designated to be a key. Lastly, there could be relationships between entities. Relationships could be 1-to-1, 1-to-n, n-to-1 or m-to-n, depending on how the entities participated in the relationship. Relationships could also have attributes that described the relationship.

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16. Rather than being used as a model on its own, the E-R model has found success as a tool to design relational databases. In addition, it was a simple process to convert an E-R diagram into a collection of tables in third normal form. Today, the ability to create E-R diagrams are incorporated into data modeling tools such as IBM InfoSphere™ Data Architect.

17. Jemerson Pedernal Object-relational model The Object-Relational (OR) model is very similar to the relational model; however, it treats every entity as an object (instance of a class), and a relationship as an inheritance.

18. Jemerson Pedernal Other data models XML is ideal to store semi-structured data. Object oriented data models are popular in universities, but have not been widely accepted in the industry; l to store semi-structured data.

19. Jemerson Pedernal 1.5 Typical roles and career path for database professionals Data Architect Database Architect Database Administrator (DBA) Application Developer

20. Jemerson Pedernal Data Architect A data architect is responsible for designing an architecture that supports the organization's existing and future needs for data management. The architecture should cover databases, data integration and the means to get to the data.

21. Jemerson Pedernal Database Architect A database architect is responsible for the following activities: Gather and document requirements from business users and management and address them in a solution architecture. Share the architecture with business users and management. Create and enforce database and application development standards and processes. Create and enforce service level agreements (SLAs) for the business, specially addressing high availability, backup/restore and security.

22. Jemerson Pedernal Study new products, versions compatibility, and deployment feasibility and give recommendations to development teams and management. Understand hardware, operating system, database system, multi-tier component architecture and interaction between these components. Prepare high-level documents in-line with requirements. Review detailed designs and implementation details.

23. Jemerson Pedernal Database Administrator (DBA) A database administrator (DBA) is responsible for the maintenance, performance, integrity and security of a database. Additional role requirements are likely to include planning, development and troubleshooting.

24. Jemerson Pedernal Application Developer A database application developer is a person in charge of developing applications that access databases. An application developer requires knowledge of the following: Integrated database application development environments (IDEs). Database plug-ins for IDEs. SQL development tools Database performance monitoring and debugging Application server environments, application deployment, application performance monitoring and debugging

25. Jemerson Pedernal Summary In this chapter, we discussed several database fundamental concepts starting with simple definitions of a database and extending to a database management system. Then, we discussed information and data models such as the network, hierarchical, and relational models. At the end of the chapter, various roles associated with the database domain were discussed.